🚀 go-pugleaf

In article <ldsoderb.724677131@reading>,
ldsoderb@susssys1.reading.ac.uk (David S. Oderberg) writes:
|>
|>Could someone please tell me whether artificial breeding/selection has
|>so far produced any news species, according to the generally accepted
|>definition/s of `species' among biologists (interbreeding capacity etc.)?
|>Even including the very latest in biotechnological achievements, has the
|>creation of new species been attained?
|>
|>I am aware of the alleged creation of plant hybrids which can't be crossed
|>with either parent species: do these, if they exist, qualify?  

There are quite a lot of cases of this, if you use the generally accepted
definition of "same species" and "different species", namely, populations of
organisms that, if brought together geographically, will merge into a single
breeding population are considered to be in the same species, while those
that will remain distinct, due to physical or behavioral reproductive isolation,
are considered to be of different species.

Consider the domestic dog, for example.  Chihuahuas and Great Danes are quite
reproductively isolated, physically.  They are considerably more distinct on
both morphological and biological grounds than Mallard and Pintail ducks,
which are generally recognized as separate species, although they freely
interbreed and hybridize in captivity.  Yes, one can mix the two populations of
dogs  by "transitive closure" using intermediate breeds of dogs, but the
situation has several natural analogs to clinal variation among closely
related species in the wild, where the ends of the cline are reproductively
distinct and considered two species, but there is a chain of hybrids that
link the two populations.

Since new "species" of dogs can essentially be created this way more or less at
will by selective breeding, taxonomists don't bother to give them all status as
separate species, which technically they are entitled to, but instead lump them
all together in the single species Canis domesticus.  From a practical
standpoint, it simply isn't useful to consider all the domestic breeds and
strains as separate species.

--PSW